1. Field of the Invention
The present invention relates to a data record medium, a data recording and/or reproducing apparatus, and a record medium determining method in particular, to those that allow the compatibility with conventional mediums to be maintained and high density mediums to be handled.
2. Description of the Related Art
In recent years, optical discs as large storage capacity record mediums have been developed. Examples of such optical discs area a CD (Compact Disc) for music information, a CD-ROM for computer data, and a DVD (Digital Versatile Disc or Digital Video Disc) for movie information. These discs are read-only discs. More recently, write-once-read-many optical discs and rewritable optical discs such as a CD-R (CD-Recordable), a CD-RW (CD-Re-Writable), a DVD-R (DVD-Recordable), a DVD+RW, and a DVD-RAM (Random Access Memory) are becoming common. Since these write-once-read-many discs and rewritable discs do not contain signals in data non-written state, they need position information (address information) unlike read-only optical discs.
In a CD-R or a CD-W, guide grooves for a laser beam are wobbled and position information or time information is successively recorded as wobble information so as to successively pre-format address information. With reference to the address information obtained from wobble information, data is written on the disc. The wobble information is a signal that is frequency-modulated with a carrier of 22.05 kHz. By demodulating the signal, the address information is obtained. This address information is referred to as ATIP (Absolute Time in Pre-grooves). The address information represents absolute addresses on the disc with time information.
The absolute addresses have a format of time information composed of minutes, seconds, and frames (MSF format). Each decimal number of minutes, seconds, and frames is represented in a binary coded decimal (BCD) notation. One second is composed of 75 frames. Absolute addresses from 00 minutes, 00 seconds, and 00 frames to 99 minutes, 59 seconds, and 74 frames can be represented. In the BCD notation, one digit of a decimal number is represented with four bits of binary numbers. Thus, the ATIP requires 24 bits.
It is preferred to increase record capacities of a CD-R and a CD-RW. As pit forming technologies, recording and/or reproducing technologies, and laser technologies (for short wavelength) are improved, high density discs (with high record capacities) can be accomplished. However, when the record capacities of a conventional CD-R and a conventional CD-RW (around 650 MB each) are doubled, a time exceeding 100 minutes cannot be represented with the conventional ATIP.
Therefore, an object of the present invention is to provide a data record medium, a data recording and/or reproducing apparatus, and a record medium determining method that allow the compatibility with conventional mediums to be maintained, address information corresponding to high density structures of mediums to be represented, and that can be used for a computer.
To solve the above-described problem, a first aspect of the present invention is a data record medium having an address representing area of a predetermined number of bits for representing time information representing minutes, seconds, and frames in a binary coded decimal notation, wherein addresses represented in a binary notation instead of the binary coded decimal notation are placed in the address representing area.
A second aspect of the present invention is a data recording and/or reproducing apparatus for allowing a first data record medium and a second data record medium to be used, the first data record medium having an address representing area of a predetermined number of bits, the address representing area containing time information representing minutes, seconds, and frames in a binary coded decimal notation, the second data record medium having an address representing area of a predetermined number of bits, the address representing area containing addresses represented in a binary notation rather than the binary coded decimal notation, a predetermined one bit or a plurality of predetermined bits of the address representing area being a predetermined value or a predetermined pattern, the data recording and/or reproducing apparatus comprising: means for reproducing data contained in the address representing area; and determining means for determining the disc that is being used is the second data record medium when the predetermined one bit or the plurality of predetermined bits of the data reproduced from the address representing area is the predetermined value or the predetermined pattern.
A third aspect of the present invention is a data recording and/or reproducing apparatus for allowing a first data record medium and a second data record medium to be used, the first data record medium having an address representing area of a predetermined number of bits, the address representing area containing time information representing minutes, seconds, and frames in a binary coded decimal notation, the second data record medium having an address representing area of a predetermined number of bits, the address representing area containing addresses represented in a binary notation rather than the binary coded decimal notation, the data recording and/or reproducing apparatus comprising: means for reproducing the addresses contained in the address representing area; and means for detecting a change of the reproduced addresses and determining whether the disc that is being used is the first data record medium or the second data record medium corresponding to the change of the addresses.
A fourth aspect of the present invention is a determining method for determining whether the disc being used is a first data record medium or a second data record medium, the first data record medium having an address representing area of a predetermined number of bits, the address representing area containing time information representing minutes, seconds, and frames in a binary coded decimal notation, the second data record medium having an address representing area of a predetermined number of bits, the address representing area containing addresses represented in a binary notation rather than the binary coded decimal notation, a predetermined one bit or a plurality of predetermined bits of the address representing area being a predetermined value or a predetermined pattern, the method comprising the steps of: reproducing data contained in the address representing area; and determining the disc that is being used is the second data record medium when the predetermined one bit or the plurality of predetermined bits of the data reproduced from the address representing area is the predetermined value or the predetermined pattern.
A fifth aspect of the present invention is a determining method for determining whether the disc being used is a first data record medium or a second data record medium, the first data record medium having an address representing area of a predetermined number of bits, the address representing area containing time information representing minutes, seconds, and frames in a binary coded decimal notation, the second data record medium having an address representing area of a predetermined number of bits, the address representing area containing addresses represented in a binary notation rather than the binary coded decimal notation, the method comprising the step of: reproducing the addresses contained in the address reproducing portion; detecting a change of the reproduced addresses; and determining whether the disc that is being used is the first data record medium or the second data record medium corresponding to the change of the addresses.
According to the present invention, addresses are represented in the binary notation rather than the BCD notation. Thus, the present invention can be applied to high density (large capacity) record mediums that require more addresses than the conventional discs. The recording apparatus according to the present invention can determine the type of a disc corresponding to the address representation. Corresponding to the determined result, characteristics of servos and RF equalizer can be adjusted corresponding to the type of a disc.